User blog:Cerne/Bringing it all together
Another blog entry...woohoo... Ideally this would be about my planet's geology but I was looking through my online email inbox for the copy of the planet's statistics (yes, this again) and I noticed it was quite outdated. And so what is the use of keeping it if it is no longer accurate? Then again, what is the use of discarding it if the parts of it that aren't outdated are still useful? Furthermore, what if this email was the only online record I have of said particular statistics? Now you know what this blog entry will be about. There isn't too much to change, actually, but for the sake of clarity, efficiency and convenience I am going to post the entire improved collection here for reference and get rid of my email. Just so I don't get mixed up when I do need to collect all of the stats and put them in a single place. Like my soon-to-be conworld article... I will start by listing what I changed, then briefly go over why I changed it as well as a few other important notes, and then re-post the revised statistics collection. Expect this entry to be (relatively) short and in mostly point-form in format. CHANGES *'Circumference:' 1.576106x10^7 m (m = metres) --> 25,761,060 metres. *'Surface area:' 2.1124069x10^14 m^2 --> 2.1124069e14 square metres - no change in the actual number, only in how it is represented. *'Density:' 7,452 kg/m^3 --> 7.452 g/cc (cc = centimetres squared). *'Surface gravity:' 9.72 m/s^2 --> 8.53 m/s^2 (equator); 9.10 m/s^2 (poles); 8.75 m/s^2 (constant/mean). *'Escape velocity:' 0.000129312 km/s --> 8.82113 km/s.(equatorial). *'Rotation velocity:' 581 m/s --> 500 m/s. *'Sidereal rotation period:' 68,928 seconds, or 19h, 8m, 48s --> 79699 seconds, or 22 hours, 8 minutes, 19 seconds. The --> arrow represents the change. Preceding it was what I had in the email and following it was what I got elsewhere that is replacing what was in the email. In some instances I changed an earlier number if a more accurate number was found in a later source, but a number would also have been changed back to something I had earlier if I didn't know where I had gotten the later number from so the change is not always from an earlier number to a later number. Sometimes, as with surface area, the actual number doesn't change but rather the form in which the number is typed has been changed. Any change at all merits listing it here. A few other notes: #Circumference was corrected by TomHChappell from the ZBB, converted into metres with this site, and then rounded up. #For some reason I have volume listed as 2.80e20 cubic metres. This may have come from bulbaquil on the ZBB, or from someone else on the ZBB, or it may have been acquired from myself. In any case, I did get a mass of 2.39e24 kg (courtesy of bulbaquil) instead of 51,359,929e7 kg which I would have gotten if I had converted my original mass of 513,599.29 Tg (Teragrams) into kilograms. If the 2.80e20 number was determined before I got the 2.39e24 number then chances are the former number was used to get the latter number. I was going to ask about this but I think I will just save the time and effort by omitting the 513,599.29 number altogether. If someone wants to correct me with my new numbers, that would be fine, but if I was wrong about circumference then I was probably wrong about volume and therefore mass as well. The idea that someone who probably knew more mathematics than I do suggested it is all the validation I need. I am not going to mention what changed in terms of volume and mass because, technically, nothing did change. #I have no idea where the previous gravity came from. None of my current numbers even go that high. I suspect it might have come from the exchange I had with Tropylium on the ZBB earlier this year but I cannot say for sure. Wherever it did come from, I don't know how I got it so I am discarding it. #I may decide to omit polar gravity and mean gravity since I don't know exactly to what degree my polar flattening is yet. I don't think it has really changed though...I came up with and proposed the 0.0315 number several times in the past. If it hasn't changed at all since that first time I tried determining it, I may leave in polar gravity and the gravitational constant/mean. #Useful fact/reminder: "e" = x10^N where "N" is the variable (for surface area this is 14). Attaching it to a number, then attaching another number onto it means you are multiplying the number by ten for as many times as is represented by the variable. For reference, 10e6 (10x10^6) = 1,000,000 or one million. Or you can see it as the number of spaces you move the decimal ahead by. In which case, (10e6 = 0.00001); likewise, (10e-6 = 10,000,000) because you are moving the decimal six spaces behind where it was originally in the numeral 10. If you took mathematics in highschool, "e" can simply represent an algebral(?) expression of 10^ or "ten to the power of..." Now I am going to list what I have for my stats to date at this moment. PHYSICAL CHARACTERISTICS *'Radius:' 4.1e6 metres (equatorial); 3.97085e6 metres (polar); 4.05e6 metres (mean). *'Flattening:' 0.0315 ... (not sure what type of measurement is used). *'Diameter:' 8.2e6 metres (equatorial). *'Circumference:' 25,761,060 metres (equatorial). *'Surface area:' 2.1124069e14 square metres. *'Volume:' 2.80e20 cubic metres. *'Density:' 7.452 g/cc. *'Mass:' 2.39e24 kilograms. *'Surface gravity:' 8.53 m/s^2 (equatorial); 9.1 m/s^2 (polar); 8.75 m/s^2 (constant/mean). *'Escape Velocity:' 8.82113 km/s (equatorial). *'Rotation velocity:' 581 m/s. *'Sidereal rotation period:' 22 hours, 8 minutes, 19 seconds; 68,928 seconds in total. *'Axial tilt:' ~2 to 5 °. ORBITAL CHARACTERISTICS *'Perihelion:' 0.5579999999999999 AU. *'Aphelion:' 0.642 AU. *'Semi-major axis:' 0.6 AU. *'Eccentricity:' 0.07 °. *'Average orbital speed:' ??? (haven't determined this yet). *'Orbital period (sidereal year):' 240.0667969545143 days. There will be a third and possibly fourth and fifth section of statistics. The third section will have things like albedo, surface temperatures, surface atmospheric pressure, atmospheric composition, atmospheric insolation (which I have already), and land-to-water ratio, among others. The fourth and fifth sections - should I decide to use them - will be stellar and satellite statistics. This may be somewhat more difficult. Or it may not. I may have other stats on my planet's sun somewhere in my blog that I have forgotten about. Finally, here is a short exerpt from the email that I am pasting here for records' sake, if for nothing else: "I left out polar gravity as well as the upper and lower limits for my planet's oblateness (flattening) because those equations required some big numbers and I do not know how to find the results using downscaled equivalents. If you feel up to it, you can doublecheck my answers using Geoff's site. I also left out the axial tilt because I am not sure in what way the polar flattening decides this, if it does at all. From the looks of it, my planet is pretty oblate compared to Earth and this might mean a very high degree of obliquity, but again I am not sure. It might be the reverse. If anyone could give me some insight on this, I would appreciate it." And that's it. Pretty sad, huh? It took me over a year to get these statistics. Mostly it involved knowing where to look but I am relieved that most of the actual equations are pretty much over with more than anything else. If it has to take a long time, I would rather that time be used looking for resources and online calculators than do-it-yourself equations...though I could understand it if others preferred it the other way around. Depends on what gets your rowboat rowing (floats your boat, sinks your ship, etc.), I suppose. In my next entry I will try to type about some actual progress as there is still a lot I want to cover. I don't know when I will get around to typing it, but at the rate I'm going right now it might not be that far off. Until then, thanks for reading. Category:Blog posts Category:Blog posts